A laughing gas-oxygen mixture, to which a defined amount of anesthetic is added in the form of a vapor, is used in many cases in the field of inhalation anesthesia. Since prior-art anesthetic respirators operate, in general, in the so-called excess gas mode, in which more gaseous anesthetic is fed into the respiratory circuit than is consumed by the patient, a certain volume of gas must be removed and disposed of via a central gaseous anesthetic exhaust unit during the use of the apparatus. An activated carbon filter is provided as the adsorbent for anesthetic vapor in a gaseous anesthetic processing unit known from DE 42 08 521 A1, and the laughing gas is decomposed into oxygen and nitrogen in a catalyst cartridge, because it is not bound by the activated carbon filter. This method of processing gaseous anesthetics is relatively expensive, because at least two purification steps are necessary.
It has been known from EP 113 023 B1 that laughing gas can be removed from a hydrogen-nitrogen monoxide gas mixture with a molecular sieve having a pore size between 0.4 and 1 nm.
However, the removal of two components from a gas mixture, laughing gas and anesthetic vapor in this case, is possible only insufficiently with the prior-art molecular sieve, because only one of the components is always adsorbed sufficiently, depending on the pore size.